The present disclosure relates generally to draw-out circuit breakers and particularly to a shutter locking arrangement for a draw-out mechanism (also herein referred to as the cassette) of an Air Circuit Breaker.
A cassette is a mounting accessory into which a circuit breaker may be installed, having terminals to which the main electrical supply lines are connected. The cassette has shutters configured to cover the terminals, preventing contact with live terminals when the breaker is withdrawn. The shutters also lift to allow the withdrawable unit (the circuit breaker) to be easily and rapidly connected to the terminals in the cassette. A racking mechanism is used to install or remove the circuit breaker from the cassette. Many cassettes utilize shutter locks, which are secondary devices mounted close to the terminals, or front panel mounted shutter locks, which comprise many components, increasing the complexity and assembly cost of the cassette.
In view of the foregoing assembly drawbacks, the art of draw-out circuit breakers would benefit from an improved shutter locking arrangement having ease of assembly.